The present invention is related to hearing systems and, more particularly, to two stage implantable microphone devices that may be utilized in hearing systems.
Conventional hearing aids are placed in the ear canal. However, these external devices have many inherent problems including the blockage of the normal avenue for hearing, discomfort because of the tight seal required to reduce the squeal from acoustic feedback and the all-too-common reluctance for hearing-impaired persons to wear a device that is visible.
Recent advances in miniaturization have resulted in hearing aids that are able to be placed deeper in the ear canal such that they are almost unnoticeable. However, smaller hearing aids bring with them new problems including troublesome handling and more difficult care.
Implantable hearing devices offer the hope of eliminating problems associated with conventional hearing aids. One requirement for an implantable hearing device or system is an implantable microphone. Prior art implantable microphones for use with hearing systems have comprised an electret microphone encased in a metal housing.
With the advent of implantable direct-drive devices for stimulating hearing, there is a great need for implantable microphones that provide excellent audio characteristics. Such implantable microphones may open the doors to a new era where implantable hearing devices replace the conventional hearing aid.